HH1: H(alpha) and [SII] Spectroscopy With Two-Dimensional Spatial Resolution
Abstract
Long-slit spectra of the Herbig-Haro object HH 1 have been obtained for several slit positions parallel and perpendicular to the axis of the HH 1/2 system. These observations (which have a spectral resolution of about 55 km/s at H-alpha) have been used to determine the H-alpha and S II forbidden-line 6717 + 6731 line proflies as a function of position in the object. The radial velocity of the center of the line profiles is always very low, lying only slightly above the errors of the measurements. However, the linewidths do have a very interesting behavior, showing two, well-defined spatial maxima. The first linewidth maximum is located on the axis of the HH 1/2 outflow, farther away from the source than HH 1F (the 'leading condensation' of HH 1). The second maximum is located in a region of low surface brightness SW of the condensations HH 1A and C. A similar behavior is obtained for both the H-alpha and the S II forbidden line. HH 1 has been modeled in the past as a single bowshock (the head of which corresponds to HH 1F) or as a group of bowshocks (one for each condensation). Both of these scenarios fail to explain the observed spatial dependence of the line profiles.
- Publication:
-
The Astronomical Journal
- Pub Date:
- September 1991
- DOI:
- 10.1086/115940
- Bibcode:
- 1991AJ....102.1147S
- Keywords:
-
- Forbidden Transitions;
- H Alpha Line;
- Herbig-Haro Objects;
- Line Shape;
- Stellar Spectra;
- Sulfur;
- Spatial Resolution;
- Spectral Resolution;
- Astrophysics;
- SPECTROPHOTOMETRY;
- STARS: PRE-MAIN-SEQUENCE